Ceria-Induced Strategy To Tailor Pt Atomic Clusters on Cobalt–Nickel Oxide and the Synergetic Effect for Superior Hydrogen Generation

Abstract

A new and reusable hybrid catalyst of Pt/CeO2–Co7Ni2Ox is fabricated readily, in which a high dispersion of Pt atomic cluster is successfully achieved by the introduction of CeO2. The oxidation states of each elemental metal in varied compositions are studied systematically to design the catalyst. The optimal Pt/CeO2–Co7Ni2Ox catalyst exhibits an extremely high specific H2 evolution rate of 7834.8 mLH2 min–1 gcat–1 and turnover frequency of 679.0 molH2 min–1 molPt–1 for the hydrolysis of alkalized NaBH4 solution. It is one of the most efficient catalysts so far, and the reason is ascribed to the lower activation energy (47.4 kJ mol–1) as we confirmed. The lower energy barrier and high performances mainly results from the ultrasmall Pt atomic clusters, which have more active sites to adsorb and break the B–H bonds in BH4– ions for the generation of negative charged H– via electron transfer, and then the H– can immediately combine with the positive charged H+ (originated from the weakened H–O–H bond on the Ce–Co–Ni oxide) to produce H2 fast.